Early puberty case study: Crystal Keast

Crystal Keast, from Kiama in New South Wales, entered puberty when she was just 10.

Her mother Jodi says it was a tough time.

"What they have is the mind of a child in the body of a woman," she said.

"She is a quiet and shy girl and going through early puberty gave her a heightened sense of self awareness, which in some ways made her feel insecure.

"I had to take her to a skin specialist a few times to deal with the acne she got when she was 10.

"So she tended to internalise it and didn't really open up about what she was going through."

But Jodi says Crystal had the support of family and friends.

She says she bought her daughter some books to read and wrote her a letter to help her understand the changes she would be going through.

"There is so much information for a child to take in when they go through early puberty. I actually wrote her a letter explaining the practicalities, which helped because she wasn't easily able to talk about it," she said.

Jodi says some of Crystal's friends were also going through the same thing.

"She was probably lucky in some ways as some of her friends were also showing signs of puberty at the same time," she said.